Kinetics and mechanisms of nucleophilic displacements with heterocycles as leaving groups. Part 8. Conductimetric and spectrophotometric rate constants for the reactions of pyridinium and related cations with piperidine in chlorobenzene
作者:Alan R. Katritzky、Yu Xiang Ou、Joan Ellison、Giuseppe Musumarra
DOI:10.1039/p29830001421
日期:——
which the spectrophotometric method fails. It gives equivalent results. NN′-Dimethylthiourea displaces heterocyclic leavinggroups at rates similar to those for piperidine. Compared with α-hydrogen, α-methyl groups render pyridine a less effective leavinggroup, whereas α-ethoxycarbonyl groups show a large rate enhancement.